Step 3.5 Flash is $0.11 cheaper per 1M input tokens (55% lower; 2.22x difference).
API cost decision in 10 seconds
Step 3.5 Flash vs DeepSeek V3 0324
Pick Step 3.5 Flash when budget and context both matter.
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Data confirmed:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Step 3.5 Flash when budget and context both matter.
On the standard 1M input plus 500K output workload, Step 3.5 Flash is estimated at $0.24 vs $0.58 for DeepSeek V3 0324, saving $0.34 (59% lower).
Cost-first pickStep 3.5 Flash
Context-first pickStep 3.5 Flash
Sample savings$0.3459%
10x traffic gap$3.45
Step 3.5 Flash is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $3.45. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Step 3.5 Flash stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Step 3.5 Flash | DeepSeek V3 0324 |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Step 3.5 Flash | $0.6 | $1.39 |
| Balanced workload | 1M input + 1M output | Step 3.5 Flash | $0.39 | $0.97 |
| Output-heavy chatbot | 1M input + 5M output | Step 3.5 Flash | $1.59 | $4.05 |
Step 3.5 Flash is $0.47 cheaper per 1M output tokens (61% lower; 2.57x difference).
Step 3.5 Flash has 98.3K more context (1.6x larger).
Step 3.5 Flash is $0.34 cheaper on the standard workload (59% lower).
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
Step 3.5 Flash has the lower input price; Step 3.5 Flash has the lower output price; Step 3.5 Flash offers the larger context window. For the 1M input plus 500K output sample, Step 3.5 Flash is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0.24 for Step 3.5 Flash and $0.58 for DeepSeek V3 0324.
Choose Step 3.5 Flash when you care most about lower input-token price, lower output-token price, and larger context window.
Choose DeepSeek V3 0324 when its provider, model quality, latency, or availability is more important than the numeric price/context winner.
- On the standard 1M input plus 500K output workload, Step 3.5 Flash is estimated at $0.24 vs $0.58 for DeepSeek V3 0324, saving $0.34 (59% lower).
- Step 3.5 Flash is $0.34 cheaper on the standard workload (59% lower).
- Step 3.5 Flash is $0.11 cheaper per 1M input tokens (55% lower; 2.22x difference).
- Step 3.5 Flash is $0.47 cheaper per 1M output tokens (61% lower; 2.57x difference).
- Step 3.5 Flash has 98.3K more context (1.6x larger).
| Feature | Step 3.5 Flash (StepFun) | DeepSeek V3 0324 (DeepSeek) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.09 | $0.2 |
| Completion Price per 1M tokens | $0.3 | $0.77 |
| Sample Workload Cost 1M input + 500K output | $0.24 | $0.58 |
| Context Window | 262.14K | 163.84K |
| Release Date | ||
| Popularity | #43 | #52 |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Step 3.5 Flash | On the standard 1M input plus 500K output workload, Step 3.5 Flash is estimated at $0.24 vs $0.58 for DeepSeek V3 0324, saving $0.34 (59% lower). |
| High-volume input processing | Step 3.5 Flash | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Step 3.5 Flash | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Step 3.5 Flash | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- DeepSeek V4 Flash (free) can replace DeepSeek V3 0324 when lower sample workload cost matters most: $0.
- DeepSeek V4 Flash can replace DeepSeek V3 0324 when lower sample workload cost matters most: $0.2.
- R1 Distill Qwen 32B can replace DeepSeek V3 0324 when lower sample workload cost matters most: $0.43.
- DeepSeek V3.2 can replace DeepSeek V3 0324 when lower sample workload cost matters most: $0.44.
- Llama 4 Scout offers 10M context with $0.23 sample workload cost.
- Owl Alpha offers 1.05M context with $0 sample workload cost.
- DeepSeek V4 Flash offers 1.05M context with $0.2 sample workload cost.
- Gemini 2.5 Flash Lite offers 1.05M context with $0.3 sample workload cost.
- DeepSeek V4 Flash · DeepSeek · #1
- Hy3 preview · Tencent · #2
- Claude Opus 4.7 · Anthropic · #3
- Claude Sonnet 4.6 · Anthropic · #4
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